MAC multiplexing and TFC selection procedure for enhanced uplink

ABSTRACT

A method implemented in a wireless communication system including a wireless transmit/receive unit (WTRU), a Node-B and a radio network controller (RNC) for quantizing multiplexed data allowed by grants to closely match a selected enhanced uplink transport format combination (E-TFC) transport block size is disclosed. The amount of scheduled and non-scheduled data allowed to be transmitted is quantized so that the amount of data multiplexed into an enhanced uplink (EU) medium access control (MAC-e) protocol data unit (PDU) more closely matches the selected E-TFC transport block size. In an embodiment, the amount of buffered data allowed to be multiplexed by at least one grant, (a serving grant and/or a non-serving grant), is quantized so that the sum of scheduled and non-scheduled data including MAC header and control information multiplexed into a MAC-e PDU more closely matches the selected E-TFC transport block size.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.60/676,345 filed Apr. 29, 2005 and U.S. Provisional Application No.60/683,214 filed May 20, 2005, which is incorporated by reference as iffully set forth.

FIELD OF INVENTION

The present invention is related to a wireless communications. Moreparticularly, the present invention is related enhanced uplink (EU)transmission.

BACKGROUND

In a Third Generation (3G) cellular system, such as the system 100 shownin FIG. 1, EU provides improvements to uplink (UL) data throughput andtransmission latency. The system 100 includes a Node-B 102, an RNC 104and a wireless transmit/receive unit (WTRU) 106.

As shown in FIG. 2, the WTRU 106 includes a protocol architecture 200which includes higher layers 202 and an EU medium access control (MAC),(MAC-e) 206, used to support EU operation between a dedicated channelMAC, (MAC-d) 204, and a physical layer (PHY) 208. The MAC-e 206 receivesdata for EU transmission from channels known as MAC-d flows. The MAC-e206 is responsible for multiplexing data from MAC-d flows into MAC-eprotocol data units (PDUs) for transmission, and for selecting proper EUtransport format combinations (E-TFCs) for EU transmissions.

To allow for EU transmissions, physical resource grants are allocated tothe WTRU 106 by the Node-B 102 and the RNC 104. WTRU UL data channelsthat require fast dynamic channel allocations are provided with fast“scheduled” grants provided by the Node-B 102, and channels that requirecontinuous allocations are provided with “non-scheduled” grants by theRNC 104. The MAC-d flows provide data for UL transmission to the MAC-e206. The MAC-d flows are either configured as scheduled or non-scheduledMAC-d flows.

A “serving grant” is the grant for scheduled data. A “non-scheduledgrant” is the grant for non-scheduled data. The serving grant is thepower ratio that is converted to a corresponding amount of scheduleddata that can be multiplexed, thus resulting in the scheduled datagrant.

The RNC 104 configures non-scheduled grants for each MAC-d flow usingradio resource control (RRC) procedures. Multiple non-scheduled MAC-dflows can be configured simultaneously in the WTRU 106. Thisconfiguration is typically performed upon radio access bearer (RAB)establishment, but may be reconfigured when necessary. The non-scheduledgrant for each MAC-d flow specifies the number of bits that can bemultiplexed into a MAC-e PDU. The WTRU 106 is then allowed to transmitnon-scheduled transmissions up to the sum of non-scheduled grants, ifmultiplexed in the same transmission time interval (TTI).

Based on scheduling information sent in rate requests from the WTRU 106,the Node-B 102 dynamically generates scheduling grants for scheduledMAC-d flows. Signaling between the WTRU 106 and the Node-B 102 isperformed by fast MAC layer signaling. The scheduling grant generated bythe Node-B 102 specifies the maximum allowed EU dedicated physical datachannel (E-DPDCH)/dedicated physical control channel (DPCCH) powerratio. The WTRU 106 uses this power ratio and other configuredparameters to determine the maximum number of bits that can bemultiplexed from all scheduled MAC-d flows into a MAC-e PDU.

Scheduled grants are “on top of” and mutually exclusive of non-scheduledgrants. Scheduled MAC-d flows can not transmit data using anon-scheduled grant, and non-scheduled MAC-d flows can not transmit datausing a scheduled grant.

The EU transport format combination set (E-TFCS) comprising all possibleE-TFCs is known to the WTRU 106. For each EU transmission, an E-TFC isselected from a set of supported E-TFCs within the E-TFCS.

Since other UL channels take precedence over EU transmissions, the poweravailable for EU data transmission on E-DPDCH is the remaining powerafter the power required for DPCCH, dedicated physical data channel(DPDCH), high speed dedicated physical control channel (HS-DPCCH) and EUdedicated physical control channel (E-DPCCH) is taken into account.Based on the remaining transmit power for EU transmission, blocked orsupported states of E-TFCs within the E-TFCS are continuously determinedby the WTRU 106.

Each E-TFC corresponds to a number of MAC layer data bits that can betransmitted in an EU transmission time interval (TTI). Since there isonly one MAC-e PDU per E-TFC that is transmitted in each EU TTI, thelargest E-TFC that is supported by the remaining power defines themaximum amount of data, (i.e., the number of bits), that can betransmitted within a MAC-e PDU.

Multiple scheduled and/or non-scheduled MAC-d flows may be multiplexedwithin each MAC-e PDU based on absolute priority. The amount of datamultiplexed from each MAC-d flow is the minimum of the current scheduledor non-scheduled grant, the available MAC-e PDU payload from the largestsupported TFC, and the data available for transmission on the MAC-dflow.

Within the supported E-TFCs, the WTRU 106 selects the smallest E-TFCthat maximizes the transmission of data according to the scheduled andnon-scheduled grants. When scheduled and non-scheduled grants are fullyutilized, available MAC-e PDU payload is fully utilized, or the WTRU 106has no more data available and allowed to be transmitted, MAC-e PDUs arepadded to match the next largest E-TFC size. This multiplexed MAC-e PDUand corresponding TFC are passed to the physical layer for transmission.

The serving and non-serving grants specify the maximum amount of datathat can be multiplexed from specific MAC-d flows into MAC-e PDUs eachEU TTI. Since the scheduled grants are based on the E-DPDCH/DPCCH ratio,the number of data bits allowed to be multiplexed per MAC-e PDU can notbe explicitly controlled only to allow certain sizes which match thelimited number of data sizes of the supported E-TFCs within the E-TFCS.

The remaining transmit power for EU data transmission determines thelist of supported E-TFCs within the E-TFCS. Since the supported E-TFCsare determined from a limited number of E-TFCs in the TFCS, thegranularity of allowed MAC-e PDU sizes will not allow for all possibleMAC-d flow and MAC-e header combinations. Therefore, since the amount ofMAC-d flow data allowed by the grants to be multiplexed into a MAC-e PDUwill frequently not match the size of one of the supported E-TFCs,padding will be applied to the MAC-e PDU to match the smallest possibleE-TFC size within the list of supported E-TFCs.

It is expected that when EU cells are operating at maximum capacity theMAC-e PDU multiplexing is frequently limited by the serving andnon-serving grants, and not limited by the largest supported E-TFC orthe WTRU EU data available for transmission. In this case, depending onthe granularity of specified E-TFCs within the E-TFCS, padding requiredto match the selected E-TFC may exceed the multiplexing block size ofMAC-d flow data including associated MAC-e header information. In thiscase, the effective data rate is unnecessarily reduced from what isallowed by the selected E-TFC and the physical resources required forits transmission.

FIG. 3 illustrates a MAC-e PDU 300. A MAC-e PDU header 302 and MAC-dflow data 304 allowed by scheduling and non-scheduling grants aremultiplexed. Among a set of supported E-TFCs, the WTRU 106 selects thesmallest E-TFC from a list of supported E-TFCs that is larger than MAC-ePDU header 302 and MAC-d flow data 304. Padding 306 is then applied tothe MAC-e PDU to match the selected E-TFC size. However, the padding 306may exceed the multiplexing block size of MAC-d flow data. In this case,physical resources used in the EU transmission are under utilized andthe effective WTRU data rate is unnecessarily reduced. Accordingly, itis desirable to have alternate approaches to multiplexing EU data.

SUMMARY

The present invention is related to quantizing the amount of multiplexeddata allowed by grants to closely match a selected E-TFC transport blocksize is disclosed. The amount of scheduled and/or non-scheduled dataallowed to be transmitted is either increased or decreased relative tothe grants so that the amount of data multiplexed into a MAC-e PDU moreclosely matches the selected E-TFC transport block size.

When the amount of scheduled data is adjusted to more closely match aselected E-TFC, the maximum amount of scheduled data to multiplex, thescheduled payload to transmit, is determined by the sum of the scheduledand non-scheduled data available to be transmitted and allowed by thegrants quantized to the next larger or smaller E-TFC size, minus theamount of available to be transmitted non-scheduled data that is allowedby the non-scheduled grants.

This quantization is applied when multiplexing is grant limited, and notlimited by the maximum E-TFC size resulting from E-TFC restriction orlimited by E-DCH data available for transmission.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a 3G cellular system.

FIG. 2 shows an EU protocol architecture in a WTRU.

FIG. 3 illustrates a MAC-e PDU generation.

FIG. 4 is a flow diagram of a process for generating MAC-e PDUs byquantizing the maximum amount of scheduled and/or non-scheduled dataallowed to be transmitted in accordance with a first embodiment.

FIG. 5 is a block diagram of a process for generating MAC-e PDUs byquantizing the maximum amount of non-scheduled data allowed to bemultiplexed in accordance with another embodiment.

FIG. 6 is a flow diagram of a process for generating a MAC-e PDU byreducing multiplexed data in accordance with another embodiment.

FIG. 7 illustrates MAC-e PDU generation using the process of FIG. 6.

FIG. 8A is a flow diagram of a process for generating a MAC-e PDU byadding additional MAC-d flow data blocks in accordance with yet anotherembodiment.

FIG. 8B is a flow diagram of a process for generating a MAC-e PDU byadding additional MAC-d flow data blocks in accordance an alternative tothe process of FIG. 8A.

FIG. 9 illustrates MAC-e PDU generation using the processes of FIGS. 8Aand 8B.

FIGS. 10A and 10B, taken together, is a flow diagram of an exemplaryprocedure for multiplexing in accordance with another embodiment.

FIGS. 11A and 11B is a flow diagram of a process for multiplexing MAC-dflows into MAC-e PDUs.

FIG. 12 is a block diagram illustrating a simplified architecture for EUmultiplexing.

FIGS. 13A and 13B, taken together, is a flow diagram of a multiplexingprocedure in accordance with another embodiment.

FIG. 14 is a flow diagram of an exemplary multiplexing procedure inaccordance with another embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereafter, the terminology “WTRU” includes but is not limited to a userequipment (UE), a mobile station, a fixed or mobile subscriber unit, apager, or any other type of device capable of operating in a wirelessenvironment. When referred to hereafter, the terminology “Node-B”includes but is not limited to a base station, a site controller, anaccess point or any other type of interfacing device in a wirelessenvironment. One potential system where the WTRU and Node-B are used isthe wideband code division multiple access (W-CDMA) frequency divisionduplex (FDD) communication system, although these embodiments can beapplied to other communication systems.

The features of the present invention may be incorporated into anintegrated circuit (IC) or be configured in a circuit comprising amultitude of interconnecting components.

The following modifications to MAC-e PDU multiplexing logic are proposedfor more efficient data multiplexing and improved radio resourceutilization for the cases where MAC-e PDU multiplexing is limited byscheduled and/or non-scheduled grants, and not limited by the largestsupported E-TFC or available EU data for transmission. The amount ofdata allowed to be multiplexed from MAC-d flows into MAC-e PDUsaccording to the scheduled and non-scheduled grants is either increasedor decreased to more closely match the next smaller or next larger E-TFCsize relative to the amount of data allowed to be multiplexed by thescheduled and non-scheduled grants

FIG. 4 is a flow diagram of a process 400 for generating MAC-e PDUs inaccordance with an embodiment. In step 405, a WTRU receives a scheduleddata grant from a Node-B and/or non-scheduled grants from an RNC. Instep 410, an E-TFC transport block size is selected based on the amountof data allowed to be multiplexed according to the scheduled andnon-scheduled grants. In step 415, the maximum amount of scheduledand/or non-scheduled data allowed to be transmitted according to thescheduled and non-scheduled grants is quantized so that the amount ofdata multiplexed into each MAC-e PDU more closely matches the selectedE-TFC transport block size.

FIG. 5 is a flow diagram of a process 500 for generating MAC-e PDUs inaccordance with another embodiment. In step 505, a WTRU receives ascheduled data grant from a Node-B and/or non-scheduled grants from anRNC. In step 510, an E-TFC transport block size is selected based on theamount of data allowed to be multiplexed according to the scheduled andnon-scheduled grants. In step 515, the amount of buffered WTRU dataallowed to be multiplexed by the at least one grant is quantized so thatthe sum of scheduled and non-scheduled data (including MAC header andcontrol information) multiplexed into each EU MAC-e PDU more closelymatches the selected E-TFC transport block size.

Alternatively, in a separate embodiment, granularity of E-TFC sizes isdefined within the E-TFCS so that the difference between E-TFC sizes isnot greater than one MAC-d PDU and the associated MAC-e header overhead.E-TFCs are defined for each possible MAC-d flow multiplexing combinationand associated MAC-e header overhead. By optimizing the E-TFCS in thisway, the padding required after MAC-d flow data is multiplexed accordingto the scheduled and non-scheduled grants will not exceed the size ofpossible MAC-d flow multiplexing block sizes.

FIG. 6 is a flow diagram of a process 600 for generating a MAC-e PDU inaccordance with another embodiment. A largest E-TFC is selected from aset of supported E-TFCs that is smaller than the size of MAC-d flow dataand MAC-e control signaling allowed by current grants 602. As a result,the selected E-TFC permits a decreased amount of data to be multiplexedonto the MAC-e PDU relative to the amount allowed by the grants, to moreclosely match the largest E-TFC size that is smaller than the amountrequired by scheduled and non-scheduled grants. The MAC-d flow data(scheduled and/or non scheduled) is multiplexed into a MAC-e PDU inaccordance with an absolute priority until no more MAC-d flow datablocks can be added within the limit of the selected E-TFC 604. TheMAC-e PDU is padded to match the selected E-TFC size 606.

FIG. 7 illustrates the decreased MAC-e PDU 700B size that more closelymatches a selected E-TFC size in accordance with the embodiment of FIG.6. A MAC-e PDU header 702 and MAC-d flow data blocks 704 a-704 c aresupported by the current scheduled and non-scheduled grants. Referringto FIGS. 6 and 7, the largest E-TFC that is smaller than the size ofMAC-d flow data allowed by current grants is selected from the set ofsupported E-TFCs (step 602). MAC-d flow data blocks, (in this example,the two MAC-d flow data blocks, 704 a, 704 b), are multiplexed into theMAC-e PDU 700B in accordance with an absolute priority until no moreMAC-d flow data blocks can be added within the limit of the selectedE-TFC size (step 604). MAC-d flow data block 704 c is not multiplexedsince it will exceed the limit of the selected E-TFC. Preferably, onlythe amount of multiplexed scheduled data is adjusted to more closelymatch the selected E-TFC size. Padding 706 is then applied to the MAC-ePDU 700B to match the selected E-TFC size (step 606). One technique forthe padding is accomplished implicitly by insertion of an end-of-dataindicator in the MAC-e PDU header information.

FIG. 8A is a flow diagram of a process 800 for generating a MAC-e PDUwhere the smallest E-TFC size is selected from the set of supportedE-TFC's that supports the amount of data allowed to be multiplexedaccording to the current scheduled and non-scheduled grants. MAC-d flowdata blocks are multiplexed into a MAC-e PDU in accordance with anabsolute priority until the maximum amount of data allowed by currentscheduled and non-scheduled grants is reached 802. The smallest possibleE-TFC is selected from a set of supported E-TFCs that is larger than thesize of the multiplexed MAC-e PDU 804. If the selected E-TFC sizeexceeds the size of the multiplexed MAC-d flow data blocks and the MAC-eheader by more than the smallest MAC-d flow multiplexing block size, addone or more additional MAC-d flow data blocks in accordance with theabsolute priority until no further MAC-d flow data blocks and associatedMAC-e header information can fit within the selected E-TFC size.

In an alternative process 850 shown in FIG. 8B, the smallest E-TFC thatsupports the amount of data allowed to be multiplexed according to thecurrent scheduled and non-scheduled grants is selected from the set ofsupported E-TFCs 852. MAC-d flow data blocks are then multiplexed into aMAC-e PDU in the order of absolute priority until the maximum amount ofdata allowed by the selected E-TFC size is reached 854. Preferably onlythe amount of scheduled data allowed by the grant is adjusted to moreclosely match the selected E-TFC, Non-scheduled MAC-d flow data that ismultiplexed may be restricted to the non-scheduled grant. Padding isthen applied to match the selected E-TFC size 856. With this scheme,data can be transmitted exceeding the scheduled and/or non-scheduledgrants.

FIG. 9 illustrates an increased size MAC-e PDU 900 that fully utilizes aselected E-TFC size that supports the current grants. A MAC-e PDU header902 and MAC-d flow data blocks 904 a-904 c are supported by the currentscheduled and non-scheduled grants. Referring to FIGS. 8A, 8B and 9, theMAC-d flow data blocks 904 a-904 c are multiplexed into a MAC-e PDU inaccordance with an absolute priority until the maximum amount of dataallowed by the current scheduled and non-scheduled grants is reached. Asshown in FIG. 9, three (3) MAC-d flow data blocks 904 a-904 c aremultiplexed as an example, and any number of MAC-d flow data blocks maybe multiplexed. The smallest possible E-TFC is selected from a set ofsupported E-TFCs that is larger than the size of the multiplexed MAC-ePDU. If the selected E-TFC size exceeds the size of the multiplexedMAC-d flow data blocks 904 a-904 c and the MAC-e header 902 by more thanthe smallest MAC-d flow multiplexing block size, one or more additionalMAC-d flow data blocks 904 d are added as shown in FIG. 9 in accordancewith the absolute priority until no further MAC-d flow data blocks andassociated MAC-e header information can fit within the selected E-TFCsize. Preferably, only scheduled MAC-d flow data is added exceeding thecurrent grant, but non-scheduled MAC-d flow data may also be added.Padding 906 is then applied to match the selected E-TFC size. With thisscheme, MAC-d flow multiplexing is optimized to take advantage of unuseddata bits that would have been filled with padding bits.

FIGS. 10A and 10B, taken together, is a flow diagram of a procedure 1000for multiplexing whereby, in advance of MAC-e PDU multiplexing, theamount of data to multiplex according to the scheduled and/ornon-scheduled grants is adjusted to more closely match the next largeror next smaller E-TFC size relative to the amount of data allowed to bemultiplexed by the scheduled and/or non-scheduled grants. FIG. 10Aidentifies a method where only the amount of scheduled data to multiplexis adjusted to more closely match the selected E-TFC.

Referring to FIG. 10A, an E-TFC restriction procedure is performed (step1005) to determine the set of supported E-TFCs including the largestpossible E-TFC size (step 1010) by considering MAC-d flow power offsetof the highest priority data available for transmission.

Still referring to FIG. 10A, if the largest possible E-TFC sizeresulting from E-TFC restriction, (considering remaining power and thehighest priority MAC-d flow power offset), is determined in step 1015 tobe less than the amount of data allowed by the scheduled andnon-scheduled grants (remaining power limited case), the maximumpossible payload for MAC-e PDU multiplexing is set to the largestpossible E-TFC size (step 1020) whereby the maximum amount of scheduleddata to multiplex is set to the amount of data specified by thescheduled grant (step 1025) and the maximum amount of non-scheduled datato multiplex is set to the amount of data specified by the non-scheduledgrant (step 1030).

Still referring to FIG. 10A, if the largest possible E-TFC sizeresulting from E-TFC restriction is determined in step 1015 greater thanthe amount of data allowed by the scheduled and non-scheduled grants(the grant limited case), the maximum amount of scheduled to multiplexis adjusted to match either the next larger or next smaller E-TFC sizerelative to the amount of available data allowed by the scheduled andnon-scheduled grants (steps, 1040, 1045).

For example, rather than setting the maximum amount of scheduled data tomultiplex to the amount of data allowed by the scheduled grant, themaximum amount of scheduled data is set to the selected E-TFC size minusthe amount of available data allowed to be transmitted by thenon-scheduled grants (step 1040), and the maximum amount ofnon-scheduled data to multiplex is set to the non-scheduled grant (step1045) for each non-scheduled data flow. These methods, or other similarmethods, result in setting the amount of multiplexed scheduled andnon-scheduled data to match the selected E-TFC size, rather than settingthe amount of multiplexed scheduled and non-scheduled data according tothe associated grants.

Preferably, only the amount of data allowed to be multiplexed fromscheduled MAC-d flows is increased or decreased to more closely matchthe selected E-TFC size. Optionally, the maximum possible payload forMAC-e PDU multiplexing is set to the size of the selected E-TFC. Othersequences of operation to pre-determine the optimal amount ofmultiplexed scheduled and/or non-scheduled data in advance ofmultiplexing are also possible.

Referring to FIG. 10B, MAC-d flows are then multiplexed in order ofpriority into the MAC-e PDU until the selected E-TFC size, the amount ofdata allowed by the scheduled and non-scheduled grants is reached, orall data available for transmission on the MAC-d flow is multiplexed. Instep 1050, the remaining total payload is set to the maximum possibleMAC-e PDU payload, the remaining scheduled payload is set to the maximumscheduled data to multiplex, and the remaining non-scheduled payload isset to the maximum non-scheduled data to multiplex.

The “remaining total payload” is the maximum possible payload resultingfrom E-TFC restriction, (i.e., the largest supported E-TFC). But it isimportant to note that this parameter is reduced for each multiplexeddata block within the multiplexing loop in step 1060. When in themaximum E-TFC limited case, this parameter will cause the exit from themultiplexing loop in step 1065. The “remaining scheduled payload” andthe “remaining non-scheduled payload” are the remaining scheduled andnon-scheduled data that are initially set to the maximum allowed tomultiplex for that type of data. Then these parameters are reduced eachtime data of that type is multiplexed. They will also cause an exit fromthe multiplexing loop in step 1065 for the grant limited case. Thehighest priority data available is selected for transmission.

In step 1055, for each scheduled channel of this priority, the minimumof the remaining total payload, the remaining scheduled payload and theavailable data on this channel is multiplexed. The remaining totalpayload and the remaining scheduled payload is decreased by the amountof the data multiplexed. In step 1060, for each non-scheduled channel ofthis priority, the minimum of the remaining total payload, the remainingnon-scheduled payload and the available data on this channel ismultiplexed. The remaining total payload and the remaining scheduledpayload is decreased by the amount of the data multiplexed.

If it is determined in step 1065 that the remaining total payload iszero, or the remaining scheduled payload and the remaining non-scheduledpayload is zero, or there is no more data available for transmission,the smallest possible E-TFC size that supports the size of themultiplexed data is selected, and padding is added to the MAC-e PDU tomatch this size if necessary (step 1070). Otherwise, the next lowerpriority data available for transmission is selected in step 1075. Itshould be noted that rather then selecting the next lower priority instep 1075, it is also possible just to select the highest prioritylogical channel that has not been serviced, and continue themultiplexing loop until all logical channels are serviced.

In another embodiment as illustrated in FIGS. 11A and 11B takentogether, a power offset of the selected MAC-d flow is identified, step1301. Using the power offset, a maximum supported payload, such as thelargest supported E-TFC that can be sent by the WTRU based on the offsetand the remaining power allowed for E-DCH data is identified. This canbe referred to as the E-TFC restriction procedure, step 1302. Avariable, “Remaining Payload”, is initially set to the maximum supportedpayload, step 1303. Based on the scheduled grant, a variable, “RemainingScheduled Payload”, is set to the largest payload that can betransmitted according to the scheduled grant and the power offset, step1304. For each MAC-d flow with a non-scheduled grant, a variable,“Remaining Non-scheduled Payload”, is set to the value of the grant,step 1305. A variable, “Non-scheduled Payload”, is the amount ofnon-scheduled data that can be transmitted and is based on a sum ofnon-serving grants and the available data on each of these non-scheduledMAC-d flows, step 1306.

If the “Remaining Payload” is larger than the sum of the amount ofavailable data allowed to be transmitted by the “Remaining ScheduledPayload”, “Remaining Non-scheduled Payload” including any MAC headerinformation and control signaling overhead, the next smaller supportedE-TFC is selected based on the sum, step 1307. If the “RemainingPayload” is not larger than the sum, the largest supported E-TFC is usedto limit the amount of multiplexed data. In the case that there is no“Scheduled Payload”, the selected E-TFC will be the largest supportedE-TFC, as the “Remaining Payload” will not be larger than the sum. Thisallows for the transfer of all “Non-Scheduled” payload unless the E-TFCis restricted to not permit this transfer.

The next smaller supported E-TFC is the largest supported E-TFC thatdoes not carry more data than the sum. In other words, the selectedE-TFC is the next smaller E-TFC based on the serving grant,non-scheduled grants, the power offset, available data, including anyMAC header information and control signaling overhead, such asscheduling information. The “Remaining Scheduled Payload” is set to thesize of the selected E-TFC, which can also be referred to as a“quantized sum”, minus the “Non-scheduled Payload” and any MAC headerinformation and control signaling overhead, step 1308. By setting the“Remaining Scheduled Payload this way, only the scheduled data isquantized. The “Non-scheduled Payload” is reserved within the selectedE-TFC according to the non-scheduled grants. Based on its priority, eachlogical channel and their associated MAC-d flow is multiplexed on to theMAC-e/es PDU, step 1309.

If the MAC-d flow of the logical channel applies to a non-scheduledgrant, the MAC-e/es PDU is filled with the MAC-d flow data from thislogical channel up to the minimum of “Remaining Non-scheduled Payload”,“Remaining Payload” or the available MAC-d flow data for that logicalchannel is filled, step 1310. The bits used to fill the MAC-e/es PDU aresubtracted from the “Remaining Payload” and the “Remaining Non-scheduledPayload”, taking into account any MAC header information and controlsignaling overhead. If the MAC-d flow applies to a scheduled grant, theMAC-e/es PDU is filled with the MAC-d flow data from this logicalchannel up to the minimum of “Remaining Scheduled Payload”, “RemainingPayload” or the available MAC-d flow data for that logical channel isfilled, step 1311. The bits used to fill the MAC-e/es PDU are subtractedfrom the “Remaining Payload” and “Remaining Scheduled Payload”, takinginto account any MAC header information and control signaling overhead,step 1312. The process is repeated for all logical channels, or untilthe “Remaining Non-scheduled Payload” and “Remaining Scheduled Payload”are both used up, or “Remaining Payload” is used up, or there is no moreavailable data to transmit step 1313. The MAC control signaling overheadsuch as scheduling information is added to the PDU and the PDU is paddedto the selected E-TFC size, step 1314.

This procedure allows the UE operation to be “deterministic” and theNode-B scheduler can therefore accurately predict how resource grantswill be used by the UE. As a result, the Node-B can more efficientlyallocate resources. It is desirable to have the amount of multiplexeddata adjusted (quantized) so that: first, physical resources are moreefficiently utilized and second increased data rates are achieved. Inorder to accomplish this, it is necessary in the grant limited case thatthe E-TFC is selected based on the current grants, and this payload sizeis used to quantize the amount of scheduled data allowed by the grantbefore multiplexing of the MAC-e/es PDU. Better physical resourceutilization and increased data rates is achieved by effecting the E-TFCselection and the multiplexing algorithm.

FIG. 12 is a block diagram illustrating a simplified architecture for EUmultiplexing. At the WTRU 1414, MAC-d flows 1403 for various logicalchannels 1402 are provided to the MAC-e/es 1404 by the MAC-d 1401. AnE-TFC selection device 1405 selects an E-TFC for EU transmissions, suchas on an enhanced dedicated channel (E-DCH) TTI basis. The E-TFCselection device 1405 receives inputs, such as scheduled grants (SG)1406, non-scheduled grants (NSG) 1407, power offsets (PO) 1408, MACheader information and control signaling overhead (MAC HEADER) 1409,buffer occupancy 1422 of MAC-d flows mapped to the E-DCH, and supportedE-TFCs (or remaining E-DCH power to perform the E-TFC restrictionprocedure). Also, “Grant Quantization” that adjusts the maximum amountof multiplexed data allowed by the resource grants can occur betweenE-TFC selection 1405 and the multiplexer (MUX) 1410. A multiplexer (MUX)1410 multiplexes the MAC-d flows 1403 for transmission according to thegrants that have been quantized to more closely match the selectedE-TFC. The MUX 1410 multiplexes the MAC-d flows 1403, adds headerinformation 1409, and adds padding, if needed, to match the selectedE-TFC size. The MAC-e PDUs 1411 produced by the MUX 1410, the selectedE-TFC, and power offset are provided to a physical layer device (PHY)1412 for transmission over the enhanced dedicated physical channel(s)(E-DPCH(s)) 1413 using the selected E-TFC.

At the base station/Node-B and Radio Network Controller (RNC) 1415, theE-DPCH(s) 1413 are received and processed by a PHY 1416 of the basestation/Node-B 1415. The MAC-e PDUs 1417 as produced by the PHY 1416 aredemultiplexed into the constituent MAC-d flows 1419 and logical channels1423 by a demultiplexer (DEMUX) 1418 of the MAC-e/es 1420. The MAC-dflows 1419 are delivered to the MAC-d 1421.

FIGS. 13A and 13B, taken together, is a flow diagram of a multiplexingprocedure 1100 in which the amount of multiplexed scheduled and/ornon-scheduled data is adjusted to more closely match the next higher ornext lower E-TFC size while performing data multiplexing. Within theorder of priority multiplexing loop shown in FIG. 10B, if the amount ofdata to multiplex is limited by the grant, the amount of data tomultiplex is adjusted according to the next larger or smaller E-TFC sizeaccording the amount of data allowed to be multiplexed by the sum of thegrants.

Referring to FIG. 13A, in step 1105, the remaining total payload is setto the maximum possible MAC-e PDU payload, the remaining scheduledpayload is set to the maximum scheduled data to multiplex, and theremaining non-scheduled payload is set to the maximum non-scheduled datato multiplex.

If the remaining scheduled payload is less than or equal to theremaining total payload, as determined in step 1110 and, optionally, theremaining non-scheduled payload and non-scheduled data is greater thanzero (step 1115), the next smaller or larger E-TFC size is selectedrelative to the amount of data already multiplexed (including MAC headeroverhead) plus the remaining scheduled payload (step 1120). Theremaining scheduled payload is equal to the selected E-TFC size minusthe amount of data already multiplexed (including MAC header overhead).

In step 1125, for each scheduled channel of this priority, the minimumof the remaining total payload, the remaining scheduled payload and theavailable data on this channel is multiplexed. The remaining totalpayload and the remaining scheduled payload is decreased by the amountof the data multiplexed.

Referring to FIG. 13B, in step 1130, for each non-scheduled channel ofthis priority, the minimum of the remaining total payload, the remainingnon-scheduled payload and the available data on this channel ismultiplexed. The remaining total payload and the remaining scheduledpayload is decreased by the amount of the data multiplexed.

If it is determined in step 1135 that the remaining total payload iszero, or the remaining scheduled payload and the remaining non-scheduledpayload is zero, or there is no more data available for transmission,the smallest possible E-TFC size that supports the size of themultiplexed data is selected, and padding is added to the MAC-e PDU tomatch this size if necessary (step 1140). Otherwise, the next lowerpriority data available for transmission is selected in step 1145. Itshould be noted that rather then selecting the next lower priority instep 1145, it is also possible just to select the highest prioritylogical channel that has not been serviced.

FIG. 14 is a flow diagram of a multiplexing procedure 1200 in accordancewith another embodiment. In the grant limited case, MAC-d flow data ismultiplexed into a MAC-e PDU until the amount of data allowed to bemultiplexed by the scheduled or non-scheduled grant associated with eachMAC-d flow is reached.

Before padding the MAC-e PDU to match the selected E-TFC size, moreMAC-d flow data is multiplexed if the multiplexing block size, (theMAC-d PDU size), is less than the amount of padding required to matchthe next larger E-TFC size relative to the amount of data allowed by thescheduled and non-scheduled grants. Preferably for the additionalmultiplexing, only scheduled data of the highest priority that isavailable for transmission is used, and non-scheduled multiplexed dataremains limited by the non-scheduled grants.

Alternatively, multiplexed data is reduced to support the next lowerE-TFC size relative to the amount of data allowed by the scheduled andnon-scheduled grants, if the multiplexing block size, (the MAC-d PDUsize), is less than the amount of needed padding to the next higherE-TFC size. Optionally padding thresholds other than the multiplexingblock size for reducing the E-TFC size can also be considered, or therequired padding to match the next lower E-TFC size being less than thelarger E-TFC by some margin could be used as a criteria for reducing theE-TFC size.

References to the amount of data multiplexed according to grants, andthe amount of data that can be multiplexed according to a selected E-TFCtakes into account MAC header information and other control signalingoverhead required in the formatting of a MAC-e PDU.

Referring to FIG. 14, the smallest possible E-TFC size is selected thatsupports the size of the already multiplexed data (including MAC headeroverhead) (step 1205). If the remaining scheduled payload and theremaining non-scheduled payload is equal to zero (optional step 1210),the remaining total payload is equal to the selected E-TFC size minusthe amount of the data already multiplexed (including MAC headeroverhead) (step 1215).

If the remaining total payload is greater than or equal to themultiplexing block size of each MAC-d flow, as determined in step 1220,for each scheduled channel of this priority, the minimum of theremaining total payload and the available data on this channel ismultiplexed, and the remaining total payload and the remaining scheduledpayload is decreased by the amount of data multiplexed (step 1225). Instep 1230, the next lower priority scheduled data available fortransmission is selected. In step 1235, padding is added to the MAC-ePDU if necessary to match the size of the selected E-TFC.

Any combination of the above embodiments may also be applied to achieveimproved multiplexing efficiency and radio resource utilization.

Although the features and elements of the present invention aredescribed in the preferred embodiments in particular combinations, eachfeature or element can be used alone without the other features andelements of the preferred embodiments or in various combinations with orwithout other features and elements of the present invention.

What is claimed is:
 1. A wireless transmit/receive unit (WTRU)comprising: a receiver configured to receive at least one serving grantand at least one non-scheduled grant, wherein the at least one servinggrant is a grant for scheduled data transmission and the at least onenon-scheduled grant is a grant for non-scheduled data transmission; amultiplexing device configured to multiplex data of medium accesscontrol dedicated channel (MAC-d) flows into a medium access controlenhanced dedicated channel (MAC-e) protocol data unit (PDU); wherein theMAC-e PDU has a size not greater than the size of the largest enhanceddedicated channel transport format combination (E-TFC) that does notexceed a first size based at least on the at least one serving grant andthe at least one non-scheduled grant, wherein the multiplexed dataincludes scheduled data for transmission; an E-TFC selection deviceconfigured to select an E-TFC for transmission of the MAC-e PDU, whereinthe selected E-TFC does not exceed the first size; and a transmitterconfigured to transmit the MAC-e PDU processed in accordance with theselected E-TFC.
 2. The WTRU of claim 1 further comprising a physicallayer device configured to receive the MAC-e PDU from the multiplexingdevice and configured to format the MAC-e PDU for transfer over anenhanced dedicated physical channel (E-DPCH).
 3. The WTRU of claim 1wherein the first size is based at least on the at least one servinggrant, the at least one non-scheduled grant, and control information. 4.The WTRU of claim 1 wherein the first size is based at least on the atleast one serving grant, the at least one non-scheduled grant, and apower offset.
 5. The WTRU of claim 1 wherein the first size is based atleast on the at least one serving grant, the at least one non-scheduledgrant, and scheduling information.
 6. The WTRU of claim 5 wherein themultiplexing device is configured to multiplex the schedulinginformation into the MAC-e PDU with the MAC-d flows.
 7. The WTRU ofclaim 6 wherein padding is multiplexed into the MAC-e PDU on a conditionthat a size of the scheduling information combined with the multiplexedMAC-d flows is less than a size associated with the selected E-TFC. 8.The WTRU of claim 7 wherein an amount of the padding is less than a sizeof a MAC-d PDU.
 9. The WTRU of claim 1 wherein the selected E-TFCsupports the size of the multiplexed data.
 10. The WTRU of claim 1wherein the multiplexing device is configured to multiplex the MACheader information and control signaling overhead into the MAC-e PDUwith the MAC-d flows.
 11. The WTRU of claim 10 wherein the multiplexingdevice is configured to multiplex padding into the MAC-e PDU on acondition that a size of the MAC header information and controlsignaling overhead combined with the multiplexed MAC-d flows is lessthan a size associated with the selected E-TFC.
 12. The WTRU of claim 11wherein an amount of the padding is less than a size of a MAC-d PDU. 13.The WTRU of claim 1 wherein the at least one serving grant originatesfrom a Node-B, and the at least one non-scheduled grant originates froma radio network controller (RNC).
 14. The WTRU of claim 1 comprising aMAC-e/es which comprises the E-TFC selection device and the multiplexingdevice.
 15. The WTRU of claim 1 wherein the first size is based at leaston the at least one serving grant, the at least one non-scheduled grant,a power offset, and scheduling information.
 16. A method fortransferring data over an enhanced dedicated channel (E-DCH),implemented in a wireless transmit/receive unit (WTRU), comprising:receiving at least one serving grant and at least one non-scheduledgrant, wherein the at least one serving grant is a grant for scheduleddata transmission and the at least one non-scheduled grant is a grantfor non-scheduled data transmission; multiplexing data of medium accesscontrol—dedicated channel (MAC-d) flows into a medium access controlenhanced dedicated channel (MAC-e) protocol data unit (PDU); wherein theMAC-e PDU has a size not greater than the size of the largest enhanceddedicated channel transport format combination (E-TFC) that does notexceed a first size based at least on the at least one serving grant andthe at least one non-scheduled grant, wherein the multiplexed dataincludes scheduled data for transmission; selecting an E-TFC fortransmission of the MAC-e PDU, wherein the selected E-TFC does notexceed the first size; and transmitting the MAC-e PDU processed inaccordance with the selected E-TFC.
 17. The method of claim 16 whereinthe first size is based at least on the at least one serving grant, theat least one non-scheduled grant, and control information.
 18. Themethod of claim 16 wherein the first size is based at least on the atleast one serving grant, the at least one non-scheduled grant, and apower offset.
 19. The method of claim 16 wherein the first size is basedat least on the at least one serving grant, the at least onenon-scheduled grant, and scheduling information.
 20. The method of claim19 wherein the scheduling information is multiplexed into the MAC-e PDUwith the MAC-d flows.
 21. The method of claim 20 wherein padding ismultiplexed into the MAC-e PDU on a condition that a size of thescheduling information combined with the multiplexed MAC-d flows is lessthan a size associated with the selected E-TFC.
 22. The method of claim21 wherein an amount of the padding is less than a size of a MAC-d PDU.23. The method of claim 16 wherein the selected E-TFC supports the sizeof the multiplexed data.
 24. The method of claim 16 wherein MAC headerinformation and control signaling overhead is multiplexed into the MAC-ePDU with the MAC-d flows.
 25. The method of claim 24 wherein padding ismultiplexed into the MAC-e PDU on a condition that a size of the MACheader information and control signaling overhead combined with themultiplexed MAC-d flows is less than a size associated with the selectedE-TFC.
 26. The method of claim 25 wherein an amount of the padding isless than a size of a MAC-d PDU.
 27. The method of claim 16 wherein theat least one serving grant originates from a Node-B, and the at leastone non-scheduled grant originates from a radio network controller(RNC).
 28. The method of claim 16 wherein the first size is based atleast on the at least one serving grant, the at least one non-scheduledgrant, a power offset, and scheduling information.
 29. A base stationcomprising: a physical layer configured to receive an enhanced dedicatedphysical channel (E-DPCH) and recover a medium access control enhanceddedicated channel (MAC-e) protocol data unit (PDU) from the receivedE-DPCH, wherein the MAC-e PDU has a size not greater than the size ofthe largest enhanced dedicated channel transport format combination(E-TFC) that does not exceed a first size based at least on at least oneserving grant and at least one non-scheduled grant, wherein the at leastone serving grant is a grant for scheduled data transmission and the atleast one non-scheduled grant is a grant for non-scheduled datatransmission; a MAC-e/es device configured to receive the MAC-e PDU anddemultiplex the MAC-e PDU into at least one medium access controldedicated channel (MAC-d) PDU and the MAC-e/es device is configured tooutput the MAC-d PDU; and a MAC-d device configured to receive theoutputted MAC-d PDU and to output at least one logical channel.
 30. Thebase station of claim 29 wherein the at least one serving grantoriginates from a Node-B, and the at least one non-scheduled grantoriginates from a radio network controller (RNC).